Abstract Detail

Systematics

Ortiz-Martí­nez, Alfredo [1], Gernandt, David S. [1].

Morphological, ecological, and molecular differentiation in Pinus patula.

Mountain formation is considered to be an important driver of vicariant speciation. We evaluated the hypothesis that the formation of the Trans-Mexican Volcanic Belt during the Quaternary promoted the divergence of the Mexican endemic Pinus patula into separate evolutionary lineages distributed naturally in the Sierra Madre Oriental and Sierra Madre del Sur. Two varieties are recognized, P. patula var. patula and P. patula var. longipedunculata, but their morphological limits and geographical distribution are poorly understood. We used multivariate statistics to analyze 14 leaf, ovulate cone, and seed characters in multiple individuals per representative population throughout their range. Using principal components analysis, we found that seven characters were needed to explain 95% of the variance. The variables with the greatest load for the first component were cone length (0.38), cone width (0.36), scale apophysis length (0.33), and peduncle width (-0.37). The characters with the greatest load for the second component were cone scale umbo width (0.61), apophysis width (0.38), and apophysis length (0.25). Using the statistical analyses as a guide, we reviewed herbarium specimens and identified a subset of localities that we considered as most likely being representative of the natural range of each variety. The geographic coordinates for each population were used to model the potential distribution of each variety and identify the most important climatic variables correlated with their distribution. The evidence for morphological, geographical, and climatic differentiation was compared to genetic evidence from low-copy nuclear gene sequences and plastomes.

1 - Instituto de Biologí­a, Universidad Nacional Autónoma de, Departamento de Botánica, Apartado Postal 70-233, Coyoacán, Ciudad de Mexico, CM, 04510, Mexico

Keywords:
Phylogeography
speciation
morphology
pine
low-copy nuclear markers.

Presentation Type: Poster
Session: P, Systematics Section/ASPT Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PSY014
Abstract ID:641
Candidate for Awards:None